Change the thread interface in runtime/platform and use it starting all threads

runtime/bin/thread_pool.cc

Index: runtime/bin/thread_pool.cc
diff --git a/runtime/bin/thread_pool.cc b/runtime/bin/thread_pool.cc
index 36960a72303b798454eb01b72b3cfa802a1044ce..cf1ec3b9d4cc941322d0857bc81f98f987613489 100644
--- a/runtime/bin/thread_pool.cc
+++ b/runtime/bin/thread_pool.cc
@@ -63,7 +63,36 @@ Task ThreadPool::WaitForTask() {
 }
 
 
-void* ThreadPool::Main(void* args) {
+void ThreadPool::Start() {
+  MonitorLocker monitor(&monitor_);
+  for (int i = 0; i < size_; i++) {
+    int result = dart::Thread::Start(&ThreadPool::Main,
+                                     reinterpret_cast<uword>(this));
+    if (result != 0) {
+      FATAL1("Failed to start thread pool thread %d", result);
+    }
+  }
+}
+
+
+void ThreadPool::Shutdown() {
+  terminate_ = true;
+  queue_.Shutdown();
+  MonitorLocker monitor(&monitor_);
+  while (size_ > 0) {
+    monitor.Wait();
+  }

[siva, 2012/01/27 18:53:17]

Threadpools always have the problem of a worker thread ending up with a wayward
task the handling of which could result in it being permanantly blocked.
In that case do we want to wait forever here for that thread to die or bail out?

[Søren Gjesse, 2012/01/30 14:42:57]

Good point. I will add a timeout and some error message to
https://chromiumcodereview.appspot.com/9212043.

+}
+
+
+void ThreadPool::ThreadTerminated() {
+  MonitorLocker monitor(&monitor_);
+  size_--;
+  monitor.Notify();
+}
+
+
+void ThreadPool::Main(uword args) {
   if (Dart_IsVMFlagSet("trace_thread_pool")) {
     printf("Thread pool thread started\n");
   }
@@ -73,8 +102,8 @@ void* ThreadPool::Main(void* args) {
       printf("Waiting for task\n");
     }
     Task task = pool->WaitForTask();
-    if (pool->terminate_) return NULL;
+    if (pool->terminate_) break;
     (*(pool->task_handler_))(task);
   }
-  return NULL;
+  pool->ThreadTerminated();
 };